Contributed Talk - Splinter SOFIA

Thursday, 14 September 2023, 17:15   (H 3006)

Far-Infrared Imaging Spectroscopy of the Galactic Centre's Circumnuclear Disk

Aaron Bryant, Alfred Krabbe, Christof Iserlohe, Christian Fischer
Deutsches SOFIA Institut, Universität Stuttgart, Germany

The inner few 100 pc of the Milky Way’s Galactic Centre serve as a rich laboratory for the study of star formation in extreme environments, and provide the unique opportunity to observe the workings of a galactic nucleus – complete with central supermassive black hole – at high resolution. Among the most pressing questions concerning the Galactic Centre is the “Paradox of Youth” – the issue of how the dense nuclear cluster of early-type stars around Sgr A* formed within the last 10 Myr. If these stars formed in-situ, then the closest molecular gas reservoir would be the Circumnuclear Disk (CND), which appears as a clumpy ring, inclined along the line of sight, surrounding the nuclear cluster with an inner radius of 1.5 pc. The structure features a number of dynamic filaments and streamers, and the physical states of the various ISM phases remain inconclusively characterised. We used the Far Infrared Field-Imaging Line Spectrometer (FIFI-LS) on board the Stratospheric Observatory for Infrared Astronomy (SOFIA) to obtain spatially resolved maps of 11 far-infrared emission lines of the region with an angular resolution approximately 4 times higher than previous published data. Together, these lines span a range of tracers of the atomic, molecular and ionised gas phases, and are used as diagnostics of the physical state of the CND. Armed with this information, we can make inferences on the role of the CND in the formation of a nuclear cluster.